Abstract: A system and method for modeling gradient coil operation induced magnetic field drift include a computer programmed to acquire a pulse sequence to be applied during an MR scan and determine a power spectrum of a plurality of gradient pulses of the pulse sequence. The computer is also programmed to calculate a drift of the magnetic field attributable to application of the plurality of gradient pulses by the plurality of gradient coils during application of the pulse sequence and apply the pulse sequence during the MR scan. The computer is further programmed to acquire MR data based on application of the pulse sequence, correct the acquired MR data based on the calculated drift of the magnetic field, and reconstruct an image based on the corrected MR data.

Abstract: In a magnetic particle imaging apparatus that forms an image of a distribution of magnetic particles based on changes in a magnetic flux generated by magnetization of the magnetic particles, modulation coils that magnetize magnetic particles present in a field free area by applying a modulation magnetic field to the field free area, and detection coils are disposed such as to suppress an influence caused by a magnetic flux of the modulation magnetic field applied by the modulation coils and included in a detected magnetic flux.

Abstract: It is proposed herein to improve the specifications of a low-noise amplifier (LNA) by integrating it in a chip. In order to cover a range of operating frequencies using a single chip, the integrated-circuit amplifier proposed herein comprises an input port configured to receive a magnetic resonance (MR) signal from a radio-frequency (RF) coil, one or more LNAs configured to amplify the received MR signal, and an output port configured to output the amplified MR signal from the one or more LNAs. The operating frequency of the RF coil depends on the field strength. The matching circuit, if present, needs to be tuned to operate at the operating frequency of the RF coil, and depends on the component values in the loop, thus on loop size. In contrast, the proposed integrated-circuit amplifier is capable of directly connecting to RF coils with different loop sizes, without the need for a matching circuit.

Abstract: In a magnetic resonance method and apparatus for determining a magnetization transfer constant a first MR signal sequence is acquired from an object being examined using a spin echo based imaging sequence, a second MR signal sequence is acquired from the object being examined using a spin echo based imaging sequence having basically identical imaging parameters to the first MR signal sequence, with the exception that the energy level of the RF pulses for exciting the magnetization in the first MR signal sequence and the energy level of the RF pulses for exciting the magnetization in the second MR signal sequence are different. The magnetization transfer constant is determined based on the signal differences between the first and second MR signal sequences.

Abstract: A method and apparatus are provided for performing an in-situ magnetic resonance imaging of an object. The method includes the steps of providing an atomic magnetometer, coupling a magnetic field generated by magnetically resonating samples of the object through a flux transformer to the atomic magnetometer and measuring a magnetic resonance of the atomic magnetometer.

Abstract: A magnetic resonance sequence model that is a formal description of a measurement sequence is used to automate measurement sequence programming. The sequence model allows a system-independent specification of the measurement sequence for execution in a magnetic resonance scanner. The sequence model is as formal as possible; it is limited to the minimum required information for description of a measurement sequence without limiting the flexibility in the sequence programming. A method for formal description of the measurement sequence describes the measurement sequence by a number of parameters to be parameterized. The parameterization of the measurement sequence can ensue automatically from the formalized description of the measurement sequence, except for a set of parameters that are still be determined.

Abstract: Described are embodiments for slice-selective excitation for MRI that utilize multiple RF transmit coils, each of which are driven with a separate independent current waveform. These embodiments allow slice-selective excitation with slice profile and excitation time similar to other single-channel excitation, but with reduction in SAR caused by the transverse component of the RF field by a factor up to the number of excitation coils.

Abstract: A transmitting device for driving a high-frequency antenna of a magnetic-resonance device using a target signal capable of being amplitude-modulated is provided. A number N of similarly embodied amplifier modules, where N is at least two, a signal-conditioning device, and a combining device for combining output signals of the amplifier modules into the target signal are provided. The signal-conditioning device generates N drive signals having a predetermined pulse frequency that consist of pulses having a length dependent on a desired target amplitude and having a phase corresponding to the desired target phase and a frequency corresponding to the desired target frequency. The pulses of the individual drive signals are mutually offset in time by, in each case, 1/N of a pulse period corresponding to the pulse frequency. Each drive signal is fed to an amplifier module.

Abstract: A method for detecting coupled RF current magnetic resonance (MR) objects in a body and determining MR risk is provided. The body is scanned with reverse circularly polarized RF. MR signals generated by coupling of the reverse circularly polarized RF with the RF current MR objects are detected. The detected MR signals are used to determine a risk value.

Abstract: An MRI apparatus is disclosed, the MRI apparatus comprising a computer programmed to apply a fluid suppression technique prior to an imaging pulse-gradient sequence, wherein the fluid suppression technique is configured to suppress signals from fluids having long longitudinal relaxation times, and apply a fat suppression technique after the fluid suppression technique and prior to the imaging pulse-gradient sequence, wherein the fat suppression technique is configured to suppress fat signals. The computer is further programmed to apply a flow suppression preparation sequence after the fat suppression technique and prior to the imaging pulse-gradient sequence, wherein the flow suppression preparation sequence is configured to suppress moving tissue signals. The computer is also programmed to apply the imaging pulse-gradient sequence, cause the RF transceiver system to acquire MR signals during the imaging pulse-gradient sequence, and reconstruct an image from the acquired MR signals.

Abstract: Techniques and systems for magnetic resonance imaging. In one aspect, preparatory pulse sequences precede alternating repetition time steady state free precession (ATR SSFP) pulse sequences to enable image acquisition before reaching a steady-state equilibrium. The design of the preparatory sequences is based on a two step process: First an oscillatory residue is expressed in terms of a window (e.g., a Kaiser-Bessel window) and scale parameters. Second the oscillatory residue is minimized to determine the scale parameters according to a desired application (e.g. ATR SSFP, optimized for fat, water, etc.) The preparation scheme described in this specification can be applied to arbitrary repetition times and RF phase cycling combinations.

Abstract: Disclosed are a high-order generalized series parallel imaging method for acquiring high spatio-temporal resolution functional magnetic resonance images and a sampling method. The higher-order generalized series parallel imaging method for acquiring high spatio-temporal resolution functional magnetic resonance images includes: performing sampling of an input image in k-space; applying a high-order generalized series (HGS) reconstruction procedure to data acquired as the sampling result to acquire a first reconstructed image; and applying a parallel magnetic resonance reconstruction procedure to the first reconstructed image to acquire a second reconstructed image.

Abstract: A method for calculating a flip angle schedule for a train of refocusing radio frequency (RF) pulses with reduced flip angles allows control of RF power deposition and use of a longer echo train. A target signal is defined for each echo in the echo train, and flip angles are then calculated from the target signals. The target signal schedule includes two phases. In the first phase, the target signals drop asymptotically to efficiently establish a pseudo-steady state at a pre-defined minimum signal level, Smin. In the second phase, the target signal is increased monotonically for the remainder of the train to a pre-defined maximum signal level, Smax. By increasing the target signal, the effect of relaxation may be reduced, decreasing blurring and ringing artifacts. Flip angles are then calculated from the target signal schedule, using a simplified method that requires no information about the tissues' relaxation properties.

Abstract: In a method of compensating for the effects of motion of an image subject during magnetic resonance imaging using phase encoding in a magnetic resonance imaging system having a number of wireless local coils and a wireless microwave transceiver array, one or more phase encoding steps are implemented to derive one or more magnetic resonance signals in the wireless coils. The signals from the phase encoding steps are upconverted to generate upper and lower sidebands of the magnetic resonance signals; and the upconverted upper and lower sideband signals are transmitted to the microwave array.

Abstract: Methods, systems and computer program products are described for providing gradient linearity correction in a magnetic resonance image. The method in one example obtains, using a simulation, a time-dependent eddy current induced magnetic gradient field produced by a gradient system in response to a gradient switching pulse. Subsequently, the method determines time-dependent eddy current harmonic response coefficients for at least one higher harmonic frequency based upon the time-dependent eddy current induced magnetic gradient field. The method then corrects the magnetic resonance image based upon the time-dependent eddy current harmonic response coefficients.

Abstract: An RF coil for MR Imaging that can change a resonance frequency easily and instantaneously in response to a nuclide to be imaged without exchange and adjustment and that also causes only small lowering of sensitivity. The RF coil has a sub coil for changing a resonance frequency of the transmitting/receiving RF coil for transmitting and receiving an MR signal between itself and a nuclide that is an object to be imaged. The sub coil is equipped with a switch, and at the time of switching-on, shifts the resonance frequency of the RF coil by changing an inductance value of the RF coil in a noncontact manner using inductance coupling.

Abstract: Described are embodiments for slice-selective excitation for MRI that utilize multiple RF transmit coils, each of which are driven with a separate independent current waveform. These embodiments allow slice-selective excitation with slice profile and excitation time similar to other single-channel excitation, but with reduction in SAR caused by the transverse component of the RF field by a factor up to the number of excitation coils.

Abstract: Accumulated spin magnetization phase within a RF MRI procedure can be used for providing an orderly k-space traversal. By operating a transmit array adapted to produce two B1 fields in alternation, where the B1 fields are substantially uniform in amplitude over a sample volume of the MRI setup, and the B1 fields have respective spatial phase distributions such that selection of a difference in spatial derivatives of the spatial phase distributions permits control over a size of a step in k-space applied by successive refocusing pulses for generating the B1 fields in alternation. Each alternating refocusing pulse issued within a T2 time causes a step through k-space in an encoding direction determined by the difference in spatial derivatives.

Abstract: A system and method is provided for simultaneously designing a radiofrequency (“RF”) pulse waveform and a magnetic field gradient waveform in a magnetic resonance imaging (“MRI”) system. The method includes determining a desired pattern of RF excitation and determining, from the desired pattern of RF excitation, a plurality of k-space locations indicative of the magnetic field gradient waveform and a plurality of complex weighting factors indicative of RF energy deposited at each k-space location. The method also includes calculating, from the determined k-space locations, the magnetic field gradient waveform and calculating, from the complex weighting factors, the RF pulse waveform that will produce the desired pattern of RF excitation when produced with the calculated magnetic field gradient.

Abstract: According to one embodiment, a MRI apparatus includes a data acquisition unit, a phase correction amount calculation unit and an image data generating unit. The data acquisition unit acquires MR signals in 3D k-space according to an imaging condition for HFI. The phase correction amount calculation unit calculates a first phase correction amount by applying processing including a phase correction based on k-space data for calculating the first phase correction amount and data compensation for a non-sampling region with the MR signals in the 3D k-space. The k-space data for calculating the first phase correction are MR signals less than the MR signals in the 3D k-space. The image data generating unit generates MR image data by applying processing including a phase correction using a second phase correction amount based on the first phase correction amount and the data compensation with the MR signals in the 3D k-space.

Abstract: According to one embodiment, a magnetic resonance imaging apparatus includes an imaging unit and data processing condition setting unit. The imaging unit is configured to acquire magnetic resonance data corresponding to a sampling region asymmetric in a wave number direction in k-space from an object to generate image data based on the magnetic resonance data by data processing including phase correction and filter processing for obtaining a complex conjugate. The data processing condition setting unit is configured to set a condition for the data processing according to an imaging condition influencing a phase distribution used for the phase correction or the phase distribution.

Abstract: A method is disclosed for suppressing and/or eliminating noise signals during magnetic resonance imaging by way of a magnetic resonance sequence including an ultra-short echo time. In at least one embodiment, the method includes a recording step for recording magnetic resonance signals of an object to be examined, especially a partial region of a patient, by way of the magnetic resonance sequence, wherein in a noise signal determination step at least one item of information about at least one noise signal of a noise element, especially of a magnetic resonance antenna element, is made available.

Abstract: Phase and gain of a transmit signal are measured at a transmitter by determining a first time delay having a first resolution at a measurement receiver between a reference signal from which the transmit signal is generated and a measured signal derived from the transmit signal by comparing amplitudes of the reference signal and the measured signal. A second time delay having a second resolution finer than the first resolution is determined at the measurement receiver between the reference signal and the measured signal based on the first time delay. The reference signal and the measured signal are time aligned at the measurement receiver based on the second time delay and the phase and gain of the transmit signal are estimated after the reference signal and the measured signal are time aligned.

Abstract: In a magnetic resonance marking system marking a flowing medium in a marking region, as well as in a magnetic resonance system with such a magnetic resonance marking system, a method to control a magnetic resonance marking system, and a method to generate magnetic resonance exposures, a radio-frequency transmission device generates marking radio-frequency signals, and a marking radio-frequency transmission coil emits the marking radio-frequency signals in the marking region. A magnetic field determination device determines a magnetic field strength in the marking region, and a control unit derives a marking transmission frequency from the determined magnetic field strength and to control the radio-frequency transmission device so that marking radio-frequency signals at the derived marking transmission frequency are emitted by the marking radio-frequency transmission coil.

Abstract: In one embodiment, an MRI apparatus includes a temperature measuring unit, a data storing unit, a pulse setting unit and an imaging unit. The temperature measuring unit measures a temperature of a gradient magnetic field coil unit at least two times. The data storing unit stores “shift data indicating a shift of a center frequency of magnetic resonance of a hydrogen atom in response to a variation of the temperature of the gradient magnetic field coil unit”, in advance. The pulse setting unit determines an estimated shift of the center frequency of the magnetic resonance according to “the variation of the temperature of the gradient magnetic field coil unit based on the measurement result” and “the shift data”, and corrects a center frequency of an RF pulse based on the estimated shift. The imaging unit performs imaging with the RF pulse whose center frequency is corrected.

Abstract: In a magnetic resonance (MR) apparatus and an operating method for the apparatus, image distortions are corrected that occur in exposures of diffusion-weighted MR images of an examination subject. A diffusion-weighted image is acquired using a first acquisition process. Another diffusion-weighted reference image is acquired using a second acquisition process that is different than the first acquisition process. The second acquisition process causes significantly smaller eddy current-dependent image distortions than the first acquisition process given the same b-value. Correction parameters to correct the image distortions of the diffusion-weighted image are determined by comparing the diffusion-weighted image with the reference image in order to determine the correction parameters such that the diffusion-weighted image can be converted into the reference image with the aid of the correction parameters.

Abstract: Means and methods for improving the MRI “image quality in an MRI imaging” apparatus comprising a non-super-conducting electromagnet and a plurality of pole pieces are provided. Said means for improving the image quality chosen from the group consisting of (a) means for reducing degradation of MRI image quality due to B0 field instability; (b) means for decreasing or otherwise correcting residual magnetization; (c) means for providing a 3D scout image; and (d) any combination of the above. These means for improving the image quality provides greater resolution of the imaged object relative to an MRI apparatus not containing such means for improving image quality.

Abstract: Techniques for designing RF pulses may be configured to produce improved magnitude profiles of the resulting magnetization by relaxing the phase constraint and optimizing the phase profiles. In one embodiment, a spinor-based, optimal control, optimal phase technique may be used to design arbitrary-tip-angle (e.g., large and small tip angle) RF pulses (both parallel transmission and single channel). In another embodiment, small tip angle RF pulses (both parallel transmission and single channel) may be designed using a small-tip-angle (STA) pulse design without phase constraint that is formulated as a parameter optimization problem.

Abstract: Methods of performing a magnetic resonance analysis of a biological object are disclosed that include placing the object in a main magnetic field (that has a static field direction) and in a radio frequency field; rotating the object at a frequency of less than about 100 Hz around an axis positioned at an angle of about 54°44? relative to the main magnetic static field direction; pulsing the radio frequency to provide a sequence that includes a phase-corrected magic angle turning pulse segment; and collecting data generated by the pulsed radio frequency. In particular embodiments the method includes pulsing the radio frequency to provide at least two of a spatially selective read pulse, a spatially selective phase pulse, and a spatially selective storage pulse. Further disclosed methods provide pulse sequences that provide extended imaging capabilities, such as chemical shift imaging or multiple-voxel data acquisition.

Abstract: For magnetic resonance imaging (MRI), a dynamic frequency drift correction method for binomial water excitation method includes collecting the reference one-dimensional navigation signal by an MRI device; acquiring one current one-dimensional navigation signal after scanning N images, wherein N is a positive integer; calculating the frequency drift according to the reference one-dimensional navigation signal and the current one-dimensional navigation signal; calculating and setting the initial phase of the next radio frequency signal by the MRI device according to the frequency drift.

Abstract: In an RF source, a digital waveform synthesizer comprises a computational module to synchronously determine a desired periodic function, f(?), within a first bandwidth portion, to which computational result there is combined an injected digital noise increment in an adjustable range of bounded amplitude, specifically selected to average over discontinuities of the DAC transfer characteristic. The combination is effected after passing the injected noise increment through a programmable digital filter forming a composite tuning word having a total bandwidth at a selected Nyquist zone and thence passing the composite tuning word through a truncation component to a DAC. The programmable digital filter is constructed to displace the spectral distribution of the injected noise increment to a portion of the total bandwidth remote from the first bandwidth portion.

Abstract: In a magnetic resonance apparatus and method to generate an image data set by means of a radial scanning of a raw data set, at least one calibration measurement is implemented for at least one predetermined spoke of the radial scan, and a gradient moment difference between an assumed gradient moment and an actually applied gradient moment is determined along the at least one predetermined spoke. Readout of all spokes of the predetermined raw data set ensues by activating multiple magnetic field gradients in spatial directions in order to respectively read out scan points of a respective spoke. The position of each scan point of each spoke is corrected depending on the gradient moment difference, by the position of the respective scan point that is assumed based on the respective activated magnetic field gradients being shifted by the gradient moment difference.

Abstract: NMR spin echo signals are acquired downhole. Principal Component Analysis is used to represent the signals by a weighted combination of the principal components and these weights are telemetered to the surface. At the surface, the NMR spin echo signals are recovered and inverted to give formation properties.

Abstract: NMR spin echo signals are acquired downhole. Principal Component Analysis is used to represent the signals by a weighted combination of the principal components and these weights are telemetered to the surface. At the surface, the NMR spin echo signals are recovered and inverted to give formation properties. Real-time displays may be used for determining formation properties and for altering the acquisition parameters.

Abstract: A method for determining amplitude and phase dependencies of radio frequency pulses that are irradiated during traversal of a defined k-space trajectory to produce a spatial pattern of the transverse magnetization in an MR experiment using at least one RF transmission antenna, is characterized in that, in a calibration step, a set of basic pulses is defined, each basic pulse is irradiated individually, the specified k-space trajectory is traversed and at least one set of basic patterns is produced by detection of the MR signals thus excited, which in a range to be examined of the object, are proportional to the complex transverse magnetization produced, wherein the k-space trajectory is traversed fully identically every time at least from the beginning of the irradiation of each basic pulse, and, in a calculation step, a defined target pattern is approximated with a linear combination of the basic patterns of a set or with a mathematical association of linear combinations, with which, within each set, the bas

Abstract: A magnetic resonance imaging apparatus generates slice images by repeating, for a plurality of consecutive repetition times, transmitting an RF pulse to a plurality of slices and scanning the slices to acquire magnetic resonance signals generated therein, in multi-slice acquisition covering the sequential slices, the sequential slices including at least a first slice, a second slice, a third slice, and a fourth slice. In the first, second, third, and fourth slices, phases of the RF pulses are alternately reversed every consecutive repetition time, and the RF pulses are transmitted to the first, second, third, and fourth slices such that the phases of the RF pulses transmitted to the first and third slices are reversed from each other in each consecutive repetition time and such that the phases of the RF pulses transmitted to the second and fourth slices are reversed from each other in each consecutive repetition time.

Abstract: The present invention provides a magnetic resonance imaging system capable of performing spectrum measurement even when a magnetic resonant frequency changes during MRS measurement. A time-varying rate of a water magnetic resonant frequency is measured in advance before the MRS measurement. The amount of change in water magnetic resonant frequency during the MRS measurement is predicted from the measured time-varying rate. With the predicted value as the reference, a transmission frequency of an RF magnetic field irradiated in a signal suppression pulse sequence, a transmission frequency of an RF magnetic field for excitation and inversion and a received frequency at the detection of a magnetic resonance signal in a sequence of the MRS measurement are respectively set. A high-precision spectrum measurement is hence enabled.

Abstract: Methods and systems are provided for modifying a pulse sequence. In one embodiment, a determination is made whether an estimated peripheral nerve stimulation (PNS) associated with a pulse sequence exceeds a PNS limit. If the estimated PNS exceeds the PNS limit, a slew rate associated with one or more axes of the pulse sequence may be reduced and the maximum gradient amplitudes for each axis of the pulse sequence may be adjusted. In one embodiment, adjustment of the maximum gradient amplitudes or local slew rate may be based upon a cost analysis performed on the pulse sequence.

Abstract: In a method and arrangement for detection of the position of an examination person on a table in a magnetic resonance system, the examination person on the table is moved relative to the magnetic resonance system, RF pulses are radiated while the examination person is moved through the magnetic resonance system, the resulting magnetic resonance signals caused by the RF pulses are detected and the position of the examination person is determined using the acquired magnetic resonance signals.

Abstract: A device that comprises an RF generator (29), an NMR transmission (20) and reception system (21) and a first control loop (28), with which the frequency fRF of the RF generator is synchronized with the resonance frequency f0 of an NMR line, wherein, from the signal of the RF generator, a train of excitation pulses (EX) of the repetition frequency fm is generated, with which nuclear spins of a certain resonance frequency of an associated NMR line are excited quasi-continuously (CW) and, in the times between the excitation pulses, the NMR signal is received (AQ), wherein the period time 1/fm is chosen to be much smaller than the relaxation time of the NMR line, preferably shorter than 1/10 of the relaxation time, and the NMR signal UD mixed down into the low-frequency range is used, with the help of the first control loop, to closed-loop-control the value of the transmission frequency (=frequency lock) or the value of the B0 field (=field lock) in such a way that the frequency and phase of the RF generator and

Abstract: NMR spin echo signals are acquired downhole. An independent component analysis is used to determine parameters of a parametric model of the T2 distribution whose output matches the measurements. The model parameters are telemetered to the surface where the properties of the formation are reconstructed. It is emphasized that this abstract is provided to comply with the rules requiring an abstract which will allow a searcher or other reader to quickly ascertain the subject matter of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims. 37 CFR 1.72(b).

Abstract: A shim arrangement for increasing the homogeneity of a magnetic field within a homogeneous field region, comprising: shim channels extending within a volume between a magnetic field generator and the homogeneous field region; at least one piece of shim material located within each shim channel; an arrangement for moving each shim piece along the corresponding shim channel; and retaining means for retaining each shim piece in position. Shimming is performed by moving shim pieces within the shim channels, with the magnet at field. No shim pieces are added to, or removed from, the shim channels during the shimming step.

Abstract: In a method and an arrangement for shimming a cylindrical magnet system, that has a cylindrical magnet having a bore therein with an axis extending therethrough, and a gradient coil assembly located within the bore, shimming is accomplished by stacking a number of planar pieces of shim material in each of said tubes, with each of the tubes having an axis parallel to the axis of the cylindrical magnet, and with the planar pieces of shim material and stacked in the tubes in respective planes that are perpendicular to the axis of the cylindrical magnet.

Abstract: Example systems, methods, and apparatus control a pMRI apparatus to produce a pulse sequence having an extended acquisition window, and overlapping phase-encoding gradients and read gradients. One example method controls a pMRI apparatus to produce a trajectory having Cartesian and non-Cartesian segments that sample in a manner that satisfies the Nyquist criterion in at least one region of a volume to be imaged. The pMRI apparatus is controlled to apply radio frequency energy to the volume according to the pulse sequence and following the trajectory and to acquire MR signal from the volume in response to the application of the RF energy. The MR signal includes a first component associated with the Cartesian segment of the trajectory and a second component associated with the non-Cartesian segment of the trajectory. The example method includes calibrating a reconstruction process using Nyquist-satisfying data from the second component.

Abstract: A method corrects for a phase error in an MR image, in which MR signals of an examination subject are acquired, complex images of the examination subject are generated, phase differences of the phase values for various image points of the complex images are established with an averaged phase value of image points from a first surrounding region of a respective image point, and a phase correction is executed dependent on how well the phase differences correspond to a predetermined phase value, where the order of the image points in which the phase correction is implemented is dependent on how well the phase values in the image points correspond to the predetermined phase value.

Abstract: A compensation device to reduce the electromagnetic field load due to the presence of a medical intervention apparatus in magnetic resonance examinations, has: a control device that has a radio-frequency input and a radio-frequency output, an injection device that is connected with the radio-frequency output and that injects the radio-frequency power delivered by the control device into the medical intervention apparatus, a measurement device that measures at least one electrical variable at the intervention apparatus, and a regulator that is connected with the control device and the measurement device. The regulator adjusts the control device to deliver the radio-frequency power so that the electrical variable at the intervention apparatus is reduced.

Abstract: A method and an RF transmit system for generating RF transmit signals for feeding an RF transmitter (14) in the form of, or comprising, one or more antenna device(s), coil(s), coil elements, or coil array(s) is disclosed. Furthermore, a multi-channel RF transmit system for feeding a plurality of such RF transmitters, especially for use as an RF excitation system in a magnetic resonance imaging (MRI) system for exciting nuclear magnetic resonances (NMR) is disclosed. A demand RF transmit signal is compared in the digital domain with an RF transmit signal and digitally corrected with respect to differences or errors between both by means of a complex predistorter (11), an adaption unit (17) and a look-up table unit (18).

Abstract: A non-linear phase correction method is provided. For the non-linear phase correction method, image information is acquired by gradient echo echo planar imaging (EPI). Reference information is acquired by spin echo EPI. The image information is corrected based on the reference information.

Abstract: To optimize in advance a desired image quality determining pulse sequence parameter incorporated in an imaging scan, a preparation scan is adopted. The preparation scan is performed with the amount of at least one desired image quality parameter changed for each of plural preparatory images, so that a plurality of preparatory images at the desired same region of the object are acquired. For example, one such image quality parameter is TI (inversion time). The acquired preparatory scan data are processed into a plurality of preparatory images for display. A desired preparatory image is then selected from the plural preparatory images displayed, and the amount of the desired parameter used for that selected preparatory image is then set for use in the pulse sequence for a complete diagnostic imaging scan. Hence the desired image quality determining parameter of the pulse sequence is caused to have an optimum value before an actual complete diagnostic imaging scan.

Abstract: To optimize in advance a desired image quality determining pulse sequence parameter incorporated in an imaging scan, a preparation scan is adopted. The preparation scan is performed with the amount of at least one desired image quality parameter changed for each of plural preparatory images, so that a plurality of preparatory images at the desired same region of the object are acquired. For example, one such image quality parameter is TI (inversion time). The acquired preparatory scan data are processed into a plurality of preparatory images for display. A desired preparatory image is then selected from the plural preparatory images displayed, and the amount of the desired parameter used for that selected preparatory image is then set for use in the pulse sequence for a complete diagnostic imaging scan. Hence the desired image quality determining parameter of the pulse sequence is caused to have an optimum value before an actual complete diagnostic imaging scan.